Spraying apparatus



April 8, 1930.

SPRAYING APPARATUS `Fi1ed Jan. 28, 1928 faggi.

c. BURDICK 1,754,145

Patented Apr. 8, 1930 UNITED STATES PATENT OFFICE CHARLES LAURENCEBURD'ICK, OFLONDON, ENGLAND, ASSIGNOR TO THE AEROGRAPH COMPANY LIMITED,OF LONDON, ENGLAND SPRAYING APPARATUS Application led January 28, 1928,Serial No. 250,276, and in Great Britain May 9, 1927.

My invention relates to machines for spraying or atomizing liquids andmay be used for distributing colours or paints on various surfaces7 orfor medical purposes or wherever a nice control is required inorder thatthe delivery of the liquid may be capable of being produced in the formof a very fine spray. Such sprays are usually made with a valve forcompressed air and a needle valve for the control of the liquid situatedin the liquid delivery port, both valves being under the control of asingle operating member, which in my invention would have two movements,a movement of depression for the air valve and a rocking movement forthe control of the quantity of liquid to be delivered. Y

My invention consists in a novel arrangement of part-s whereby the air`valve is kept open until the liquid valve is practically closed thuspreventing liquid which is not thoroughly atomized from being thrown outon to the surface which is being operated upon. i

The invention further consists in means for setting the liquid valve todeliver a defi nite small quantity whenever the air valve is opened;this is accomplished by providing a regulating de vice or stop by meansof which the needle valve is held back from completely closing thedelivery port. i

A further feature of the invention consists in an arrangement of thefulcrum and the operative point of the finger lever in such a mannerthat the delivery of the liquid into the escaping jet of compressed airis at iirst very gradual and increases in volume as the finger lever isdrawn back, thus giving the ficiency in operation is obtained, provisionfor cleaning and repair is facilitated and economy of production isobtained.`

The invention is illustrated in the accom panying drawing in which Fig.'l represents the device in cross section and Fig. 2 is a detail of thevalve controlling device.

Referring now to the form illustrated, the spray comprises a hollow bodyl having a cup or receptacle 2 for liquids and a handle portion 3.Underneath the body is formed a boss l having a channel 5 for compressedair and an internal thread 6 for the attachment of` an air valve casing7 to which is secured a nipple 8 for attachment to the com iressed airconduit. Opposite the boss a the ody is provided with a cavity 9surmounted by a slot l0 in the upper wall thereof. The forward openingof the body is threaded to receive the liquid and air delivery nozzleincluding the seating 11 for the needle valve l2 which controls theliquid supply and passes through a gland 13 in the forward part of thecavity 9. Secured to the needle valve is a squared abutment block 14,the rear portion of which provides an abutment for the valve controllingspring 15. Within the cavity 9 is slidably mounted a valve controlmechanism shown separately inFig. 2. This generally comprises acylindrical casing 2O having an upper slot 2l and a lower slot 22 andformed as an extension to a block 23 having a squared hole 24 to receivethe abutment 14; and provided with a forwardly-extending cam-shapedmember 25 comprising a small bent lug or strip.

The valve controlling` member comprisesa finger disc 2G secured to apair of slotted arms 27 articulated by means of a pivot 28 to an airvalve operating rod 29 having a reduced lower end 30 which is slidablewithin the lower slot 22. A pivot pin 81 slides within the slots 32 ofthe arms 27 and supports a neddle valve operating plate 33 having aslot33 in its transverse face to receive a camshaped member 25. The slottedarms 27 support a transverse abutment pin 35 carrying a roller 36 whichnormally lies in front of the end ofthe cam-shaped member 25.

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lVhen the parts are assembled as shown in Fig. 1, the air valveoperating rod 29 is housed within a tube 40 having an upwardly extendinglug 41 projecting into the. slot` 22 and adapted to serve as a fulcrumto the lower end of the shoulder plate 33. It is an important part ofthe invention that the front end 14a of the squared abutment block 14 onthe needle valve 12 is rounded as illustrated in Fig. 1. The air valve50 in the casing 7 is spring controlled and carries a pin 5l adapted tobe engaged by the reduced nd 30 of the rod 29 as clearly shown in ifr.1.'

n angle piece 52 having a bifurcated lower end 53 is secured to theblock 23 by means of a grub screw and is engaged in a groove 54 formedin the head of a screw 55 adapted to be adjusted in a threaded hole inthe body 4.

The operation of the device is as follows, the parts lying in theposition illustrated in Fig. 1 in which case the liquid valve and theair valve are shut.

The finger plate 26 is depressed forcing down the rod 29 and opening theair valve 50. Until this movement is completed the arms 27 cannot berocked rearwardly owing to the engagement of the roller 36 with thecam-shaped member 25, so that the liquid valve cannot be opened untilthe air valve is fully released. Conversely the liquid valve must shutwhile the air valve is still fully opened, thus preventing liquid whichis not thoroughly atomized from being thrown out on to the surface whichis being operated upon in a spot or blob.

Vhen the air valve is fully opened the arms 27 are rocked in a rearwarddirection about the pivot 28. The pin 31 has by this time ridden to thetop of the slots 32 and the rearward rocking movement of the arms 27causes the shoulder plate 33 to retract the abutment block 14 and needlevalve 12 thus opening the liquid delivery port. During this movement,the shoulder plate 33 fulcrums about the projection 41 and it will berealized that owing to the curvedA end face 14d of the abutment block 14the contact between the plate and the block gradually shifts from thelower part of the face to the upper part of the face so that for a givenincrement of displacement in the rearward direction of the plate 33, theneedle valve willbe opened by a progressively increasing amount. Theinitial opening therefore of the liquid delivery valve is at first verygradual, but increases more rapidly as the finger plate is drawn furtherbackwards.

It will be appreciated that the front abutment for the finger platecomprises the front edge of the slot 21 and that consequently if theblock 23 and cylinder 20 are drawn back by the intermediary of the fork53 by withdrawing the screw 55 the slotted arms 27 will be rocked so asto open more or less the valve 12 and this part of the appliance isaccordingly brought into use when it is desired either to maintain theliquid delivered at a fixed small value for a prolonged time oralternatively to provide a minimum delivery in connection with thevariable use of the device.

I claim l. In a spray device havingindependent air and liquid controlvalves, a control member mounted for movement in one direction tooperate one of the valves and for movement in another direction foroperating the other of said valves, and means whereby the control memberis locked against movement in one of such directions until its movementin the other of suoli directions has been accomplished.

2. A spray device including independent air and liquid control valvesand a control member for said valves, said member being mounted forlongitudinal movement to control the air valve and for swinging movementto control the liquid valve, and means whereby the control member islocked against swinging movement to govern the liquid control valveuntil its longitudinal movement for controlling the air valve has beenaccomplished. Y

3. A spray device including independent air and liquid control valvesand a control member for operating said valves, said control memberhaving a longitudinal movement to open the air valve and a swingingmovement to open the liquid valve, and means to lock the control memberagainst swinging movement to open the liquid valve until longitudinalmovement of such control member to open the air valve has beenaccomplished, said locking means serving to hold the air valve openthrough the control member in any position of the controlV membertending to hold the liquid valve open.

4. A spray device including independent air and liquid control valvesand a control member for operating said valves, said control memberhaving a longitudinal movement to open the air valve and a swingingmovement to open the liquid valve, and means to lock the control memberagainst swinging movement to open the liquid valve until longitudinalmovement of suchV control member to two distinct movements to open saidvalves,

a cam-shaped member, an axially slidable rod to open the air valve, anoperating member for said liquid valve having pivotal and slidvalve, andmeans for adjustably connecting ing connection with said rod, means onsaid the cylindrical element to the hollow body rod to engage saidcam-shaped member and to adjust the element relative to the body.

prevent rocking movement when said rod and operating member are in onerelation, and said cam-shaped member preventing the change in relationof said rod and operating member when said rod has been depressed andthe operating member has been rocked.

6. In a spray device for spraying or atomizing liquid, a body member,air and liquid control valves operated by a rocking finger piecearticulated to a pivot slidable in said body member, a cam-shaped memberiiXed relatively to said body member and an abutment on the finger pieceto normally engage said canrshaped member to prevent rocking movementoi' said finger piece when the pivot thereof is in a predeterminedrelation and to engage said abutment when the linger piece has beendepressed and rocked to prevent lift of the abutment.

7. A spray device including a hollow body, an air valve for controllingthe passage of air therethrough, a liquid valve for controlling thepassage of liquid therethrough, and control mechanism for said valvesincluding a cylindrical element designed to seat in a recess in thebody, a control member mounted for longitudinal and swinging movement insaid element, an operating rod connected to the control member to engageand operate the air valve in the longitudinal movement oi the member, acam-shaped member carried by the element, and a stop on the controlmember to engage the cam-shaped member and prevent swinging movement ofthe control member when said control member is in normal position, saidstop moving below the camshaped member following longitudinal movementof the control member to permit swinging movement of such control memberfor operating the liquid governing valve.

8. A spray device including a hollow body,

' an air valve for controlling the passage of air therethrough, a liquidvalve for control ling the passage of liquid therethrough, and controlmechanism for said valves including a cylindrical element designed toseat in a recess in the body, a control member mounted for longitudinaland swinging movement in said element, an operating rod connected to thecontrol member to engage and operate the air valve in the longitudinalmovement of the member, a cam-shaped member carried by the cylindricalelement, and a stop on the con trol member to engage the cam-shapedmember and prevent swinging movement of the control member when saidcontrol member is in normal position, said stop moving below thecam-shaped member following longitudinal movement of the control memberto permit swinging movement of such control member :for operating theliquid governing In testimony whereof I aix my signature.

CHARLES LAURENCE BURDICK.

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